Refer to Exercise 99.

a. Justify why L can be approximated by a Normal distribution.

b. Use a Normal distribution to estimate the probability that 15 or more students in the sample are left-handed.

Exercise 99.

A federal report finds that lie detector tests given to truthful persons have probability 0.2 of suggesting that the person is deceptive.11 A company asks 12 job applicants about thefts from previous employers, using a lie detector to assess their truthfulness.